Elevator systems include an elevator car that moves vertically to carry passengers, cargo or both to various levels within a building or structure. There are different arrangements for allowing passengers to request elevator service. One or more service call fixtures are strategically located to allow passengers to place their service requests. Some service call fixtures are considered hall call fixtures and are typically located near a hoistway door that provides access to an elevator car. Hall call fixtures typically have up and down selection buttons that allow an individual to indicate a desire to travel to another level above or below the level at which the hall call fixture is located. Other service call fixtures, such as destination entry devices, allow an individual to input information such as a desired floor level in a building to which the individual desires to travel.
Regardless of the type of fixture that is employed, it is necessary to facilitate accurate communications between the fixtures and an elevator system controller that is responsible for determining, among other things, the particular fixture (e.g., location) from which a service call is placed. Without knowing which fixture is used to make a service request, it is typically not possible to provide an expected quality of elevator service.
The typical approach to informing a controller about the particular fixtures includes providing unique addresses to each fixture. By recognizing an assigned address, the controller is able to determine from which fixture a service call was placed and to arrange for elevator service, accordingly.
Typical addressing procedures are time-consuming, labor-intensive and prone to installer error. Typical addressing occurs during elevator system installation. An installer has to manually set or configure each fixture to provide it with a unique address according to a predetermined pattern that will be recognizable by the controller. For example, an installer has to manually set a plurality of addressing switches or to manually set jumpers (e.g., wire loops) to set an address for each fixture. That process is time consuming and includes significant opportunity for installer error. If any error is made, the controller will not be able to recognize all of the fixtures as planned. Unfortunately, an installer typically cannot determine whether an error was made until the entire system is powered up and the controller fails to initialize operation of the system because of such an error. Determining which of the fixtures has been set wrong can be very difficult. Such a debugging process introduces additional time, labor and expense into an elevator system installation process.
One suggestion for automating such a process is made in U.S. Pat. No. 5,914,957. In that document a master controller communicates with a series of nodes to automatically provide address information to the nodes in sequential fashion.